Neural plasticity in the lateral nucleus of the amygdala (LA) is believed to underlie the acquisition and retention of Pavlovian fear condition. One candidate mechanism for this plasticity is associative long-term potentiation (LTP), The goal of the research described here is to assess the possible role of metabotropic glutamate receptors (mGluRs) in associative LTP in the LA. While much has been learned about the roles of mGluRs in plasticity in other regions of the brain, relatively little is known about their contribution to amygdala function and plasticity. In vitro studiers will assess the contribution of mGluRs to both the input specificity of LTP, as well as the temporal integrations of inputs to the LA. Finally, Immunohistochemical studies, combined with electron microscopy, will identify the subcellular distributions of the group I mGluRs. These studies should provide insight into the contributions of mGluRs to synaptic plasticity in the amygdala.